Prevalence of occupational hypersensitivity pneumonitis: a systematic review and meta-analysis

In this meta-analysis, we aimed to evaluate the prevalence of occupational hypersensitivity pneumonitis (OHP) among different occupations globally. Our search was conducted on MEDLINE via PubMed, Scopus, Web of Science, and Cochrane CENTRAL from inception to September 2023. Eligible studies were observational in nature and focused on several specific occupations. A total of 46 articles were included (n = 2,826,420 participants). The overall prevalence of OHP was found to be 4.2% (95% CI: 2.1% to 8.0%), but this varied significantly based on occupation and geographic location. Printers had the highest OHP prevalence at 57.14%, followed by tobacco workers (26.32%), and water-related workers (24.10%). South America showed the highest prevalence of 16.71%, compared to Asia (15.19%), and North America (8.52%). Significant variations in OHP prevalence by occupation and region were found, with the highest rates in printers and tobacco workers. Age and smoking were identified as contributing factors to the prevalence variability.